Projectile.



J. H HARiJCASTLE.

PROJECTILE.

APPLICATION FILED 050.30, 1913.

1,178,516. Patented Apr. 11,1916.-

1 n5 Wm FATE I I JOHN HERSCHEL HARDCASTLE, OIE BRISTOL ENGLAND, ASSIGNORIO BRITISH AND OFFICE.

COLONIAL AEROPLANE COMPANY LIMITED, 013 BRISTOL, ENGLAND.

PBOJECTILE.

Specification of Letters Patent.

Patented Apr. 11, 1916.

Application filed December 30, 1913. Serial No. 809,573.

To all whom it may concern:

Be it known that I, JOHN HERSCHEL HARDCASTLE, a subject of the King ofEngland, residing at Bristol, England, have invented certain new anduseful Improvements in Projectiles, of which the following is aspecification. This invention has for its object to pro -'vide a new andimproved projectile for rifled small-arms or ordnance which, whensuiiiciently rotated, offers less resistance to the air and has, underequal circumstances, a greater range than the projectiles at present inuse. This projectile will be sufficiently rotated if it be givena spinin accordance with the tables already in'common use for determining thispoint. It also, in flight, describes a flatter trajectory and requiresless wind allowance.

a part of this specification, Figures 1, 2 and 3 are longitudinalsectional views of projectiles embodying my invention. Figs. 4 5, 6, 7,8 and 9' are views partly in side elevation and partly in longitudinalsection illustrating other embodiments of the invention. Fig. 10 is alongitudinal sectional view showing another modification, and Figs. 11and 12 are views partly in longitudinal section and partly in sideelevation showing two more modifications.

Referring now to Figs. 1, 2, 3 and 4, the projectile l is so constructedthat its guiding portion 2 (which is preferably cylindrito one-half (seeFig. 2) of the total length of the projectile, and is situated at therear thereof. The head of the projectile is, in section, ogival,conical, paraboloid, or the :0 like, or the head may be built up ofconoid'al sections. The curves of the head L are shown, in Figs. 1 to4:, as ogival, and are of a radius a of from 9 to 36 calibers c. The

head, whatever its sectional contour, is from three to six calibers inlength. In comb1n-' ing a guiding portion and point together to form aprojectile so that the dimensions of the two parts lie within therespective limits hereinbefore stated, I-do not intend that thedimensions chosen for the two parts should In the accompanying drawings,formingcal) occupies from one-eighth (see Fig. l)-

jectile, be added, a projectile of twelve calibers length will resultwhich is useless, and I make no claim to such a projectile. On thecontrary, in applying the limits to each portion, while I wish theguiding portion to be made as short as is consistent with giving by itsmeans satisfactory spin to the pro ecti e from the rifling, I prefer notto employ a guiding portion greater than two calibers long and in nocase are the proportions of the separate parts to be such that theover-all length of the projectile is greater than seven calibers. Thetip of a projectile is preferably as sharp as possible. A projectile mayalso be constructed in accordance with the present invention with itsheadof a length as above described, but the said head, instead of beingcurved as shown in Figs. 1 to 4, may be in the form of one or moretruncated cones having one coneshaped piece at its tip. illustrated inFig. 5 there are shown three truncated cones 3, 4 and 5, and onecomplete cone 6, but I do not limit myself to this or any number oftruncated cones, though, whatever their number, the longitudinal sectionof the series is substantially the same as though a continuous curve(such, for instance, as shown in dotted lines in Fig. 5.) had beenemployed.

Another modification of the present invention consists in providing aprojectile having a head of a length as above described, but wherein thecontour of said head is either that of a cone, as shown in Fig. 6, orpartially conical andpartially ogival, as shown in Figs. 7 and 8, or itmay be partially conical and have a tip the curves of which are convexto the longitudinal axis, as shown in Fig. 11, or may be partiallyogival and have a tip the curves of which are convex to the longitudinalaxis, as shown for example in Fig. 10.

By a still further modification of the present invention, a. projectilemay be constructed with a head which is partially conical and partiallycurved convex to'its longitudinal axis, and with a cone 7 at the tip,

as shown for example in Fig. 12.

A projectile constructed in accordance with any of'the foregoingexamples may have its guiding portion tapered for part of its length,as-shown, for example, in Fig. 9,

the said taper being employed for reducing barrel-friction or soadjusting weight as to In the example cause the center of gravity to lieat a predetermined spot, or the like.

' A projectileaccording to my invention is preferably composed of amaterial strong enough to resist any tendency on the part of thepropelling gas to so compress the rear portion as to deform appreciablythe curves of the head.

- the tables at present commonly use for The term guiding portion usedin the foregoing specification refers, when applied to projectiles foruse with small-arms, to that portion thereof which bears rifling marksafter having been fired; when applied to projectiles for use forordnance, it

refers to'that portion thereof which extends from the driving band towhere the effective point of the projectile begins.

A projectile constructed in accordance with this invention will besufiiciently rotated by rifling made in accordance with of the saidpoint of such length that the length :of the point bears to the entireoverall length of the bullet a value lying between 0.5 and 0.7 25, theparts being so chosen that the said entire. overall length does notexceed seven calibers. I

'2. In afpointed projectile the combination of a point-portionwhosediameter throughout is'less than the caliber of'the rifle it isintended to be used in and whose length times the said caliber andafportion to the rear of the said point of such length that the lengthof the point bears to the entire overall length of the bullet a valuelying between 0.54 and 0.725, the parts being so chosen that the saidentire length does not exceed seven calibers.

3. In a pointed projectile the combination of a point-portion whosediameter throughout is less than the caliber of the rifle it is intendedto be used in and whose length is between three times and four times thesaid caliber and a portion" to the rear of the said point of such lengththat the length of the point bears to the entire overall length of thebullet a value lying between 0.06 and 0.7 25, the parts being so chosenthat the said entire overall length does not exceed seven calibers.

4. In a .pointed projectile the combination of'a point-portion whosediameter throughout is less than the caliber of the rifle it is intendedto be used in and whose length is between 3.5 times and 3.6 times thesaid caliber and a portion to the rear of the said point of such lengththat the length of the point bears to the "entire overall length of thebullet a. value lying between 0.59 and 0.65, the parts being so chosenthat the said is between three times and four-and-a-half entire overalllength-does not exceed seven k calibers.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JOHN HERSCHEL HARDOASTLE.

EFFIE J. FUssELL.

